291
Algae A variety of plant without distinguishable tissues
Algal bloom Sudden rise in algal growth
Alkali rain Atmospheric precipitation with elevated pH
Allergen Material that causes an allergic reaction
Alpha particle A particle charged positively released by atoms undergoing radioactive decay
Alternating electric current (Normally termed as alternating current) Electric
current that reverses its direction numerous times a time period
Ambient air Any unconfined part of the atmosphere
Ambient air quality Outdoor air quality in the environment
Amensalism Interaction in which the one organism has a negative effect on another,
while other organism species is unaffected
Ampere Unit of electric current
Amplitude of wave The maximum displacement of a vibrating particle
Anaerobic A processes carried out in anaerobic condition
Anaerobic Absence of oxygen
Anesthesiology Science as well as practice of giving anesthetics (substances to
stop patients feeling pain
Anatomy Specialty of medical science that deals with the bodily structure of living
beings
Animalia (Animals) Eukaryotic multicellular organisms that obtain nutrition from
organic sources
Anion Negatively charged ions
Anthropogenic Anything consequential from human activity
Anthropogenic emissions Emissions due to human activity
Aquifer A geological formation, which has ability that can transmit/store water
Archaebacteria/Archaea Group of prokaryotic organisms that have different
molecular characteristics making them different from bacteria and eukaryotes
Archipelago Cluster of islands formed tectonically
Arid region Area with low rainfall (usually less than 250 mm per year)
Arithmetic mean An average of values in a dataset
Ash Noncombustible residue generated in combustion process
Asthma A lung disease that causes the bronchial tubes of lungs narrow, making it
difficult to breathe
Atmosphere The layer of gas surrounding the Earth
Atom Smallest component unit of matter that has the same properties of a chemical
element
Atomic mass number Sum of the numbers of protons as well as neutrons
Atomic number Atomic number is the number of protons in the nucleus of an
atom of the element
Avalanche Snow ice that slides down a mountainside due
Avogadro’s number (Avogadro’s constant) Each mole will have approximately
the same number of elementary entities that is called Avogadro’s number
Background level Concentration of a chemical in the environment
Bacteria A type of unicellular microscopic living organisms
Glossary
Algae A variety of plant without distinguishable tissues
Algal bloom Sudden rise in algal growth
Alkali rain Atmospheric precipitation with elevated pH
Allergen Material that causes an allergic reaction
Alpha particle A particle charged positively released by atoms undergoing radioactive decay
Alternating electric current (Normally termed as alternating current) Electric
current that reverses its direction numerous times a time period
Ambient air Any unconfined part of the atmosphere
Ambient air quality Outdoor air quality in the environment
Amensalism Interaction in which the one organism has a negative effect on another,
while other organism species is unaffected
Ampere Unit of electric current
Amplitude of wave The maximum displacement of a vibrating particle
Anaerobic A processes carried out in anaerobic condition
Anaerobic Absence of oxygen
Anesthesiology Science as well as practice of giving anesthetics (substances to
stop patients feeling pain
Anatomy Specialty of medical science that deals with the bodily structure of living
beings
Animalia (Animals) Eukaryotic multicellular organisms that obtain nutrition from
organic sources
Anion Negatively charged ions
Anthropogenic Anything consequential from human activity
Anthropogenic emissions Emissions due to human activity
Aquifer A geological formation, which has ability that can transmit/store water
Archaebacteria/Archaea Group of prokaryotic organisms that have different
molecular characteristics making them different from bacteria and eukaryotes
Archipelago Cluster of islands formed tectonically
Arid region Area with low rainfall (usually less than 250 mm per year)
Arithmetic mean An average of values in a dataset
Ash Noncombustible residue generated in combustion process
Asthma A lung disease that causes the bronchial tubes of lungs narrow, making it
difficult to breathe
Atmosphere The layer of gas surrounding the Earth
Atom Smallest component unit of matter that has the same properties of a chemical
element
Atomic mass number Sum of the numbers of protons as well as neutrons
Atomic number Atomic number is the number of protons in the nucleus of an
atom of the element
Avalanche Snow ice that slides down a mountainside due
Avogadro’s number (Avogadro’s constant) Each mole will have approximately
the same number of elementary entities that is called Avogadro’s number
Background level Concentration of a chemical in the environment
Bacteria A type of unicellular microscopic living organisms
Glossary